Data from the National Survey of Oral Health in U.S. Employed Adults and Seniors: 1985-1986 were analyzed to introduce a new approach to the description of tooth loss patterns. A new typology was developed called tooth loss and prosthetic treatment (TLPT). In this typology, dental arches are classified into eight mutually exclusive, exhaustive categories. These categories relate the extent and location of missing teeth in the arch to one another and to the teeth that remain while providing some insight into the clinical options available to restore function.